Title: Standard operating procedure for testing
specific optical rotation of a given sample by using Polarimeter.
1.0
OBJECTIVE:
To lay down the procedure for testing
specific optical rotation of a given sample by using Polarimeter.
2.0
SCOPE:
This shall be applicable to the
Polarimeter of Quality Control Laboratory.
3.0
RESPONSIBILITY:
3.1 Technical Assistant/ Helper.
3.2 Q.C Analyst.
4.0
ACCOUNTABILITY:
4.1 Manager-Quality Control.
4.2 Head of the Q.C Department.
5.0
MATERIAL AND EQUIPMENT:
5.1 Polarimeter.
5.2 Analytical weighing balance.
5.3 Sample solution as specified in
monograph.
5.4 Solvent as specified in monograph.
6.0
PROCEDURE:
6.1 Firstly clean the Polarimeter with
clean dry cloth, according to SOP.
6.2 Operate the Polarimeter according to
SOP.
6.3 Determine the zero of the Polarimeter
and the angle of rotation of polarized light at wavelength of D-line of sodium
(λ=589.3nm) at 20±0.5oC, unless otherwise prescribed.
6.4 Measurements may be carried out at
other temperatures only where monograph indicates the temperature correction to
be made to the measured optical rotation.
6.5 Determine the zero of the apparatus
with tube closed; for liquids the zero is determined with tube empty and for
solids filled with prescribed solvent.
6.6 Method:
6.6.1 Weigh the sample by using weighing
balance, operate it according to SOP.
6.6.2 Prepare the sample solution as
specified in monograph by using appropriate solvent quantity.
6.6.3 Fill the Polarimeter tube with blank
solution and determine the observed optical rotation.
6.6.4 Similarly, fill the Polarimeter tube
with sample solution and determine the observed optical rotation.
6.6.5 Note down the values in annexure 1.
6.7 Calculate the specific optical rotation
by using formula:
[α]λ T = α/lc
7.0
REVISION LOG:
|
Revision No. |
Effective Date |
Reason |
|
00 |
|
New
SOP |
8.0
REFERENCES:
8.1
The British Pharmacopoeia. Vol V., Official Monograph / Determination of optical rotation and
specific optical rotation: 2015, pp. 244.
9.0
ANNEXURES:
Annexure
1: Observations and calculations.
Annexure: 1
Observations and calculations
Instrument:
___________________
Date: _______________
Model:
_______________________ Length of
Polarimeter tube: ________________
Sample:
________________________________g.
Solvent:
________________________________ml.
Concentration
of sample solution: ____________g/ml.
Blank solution:
|
Sr.# |
Blank
solution |
Temperature
|
Optical
rotation (α) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Average: _______________
Optical
rotation of blank solution: _______________
Sample solution:
|
Sr.# |
Sample
solution |
Temperature
|
Optical
rotation (α) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Average: _______________
Optical
rotation of sample solution: ______________
Optical rotation of substance = Blank solution - Sample
solution.
Specific
optical rotation of sample solution by using formula:
[α]λ T
= α/lc
Result:
________________
Remarks: ________________________________________________